Endocrinology, Vol 122, 2371-2378, Copyright © 1988 by Endocrine Society

ARTICLES

Vitamin D-dependent calcium binding protein in rat uterus: differential effects of estrogen, tamoxifen, progesterone, and pregnancy on accumulation and cellular localization

ME Bruns, JG Overpeck, GC Smith, GN Hirsch, SE Mills and DE Bruns
Department of Pathology, University of Virginia Medical School, Charlottesville 22908.

The present studies were undertaken to characterize the expression of calcium binding protein (CaBP or calbindin-D9k) in uterine tissues. Using immunohistochemical techniques, calbindin-D9k was localized to the uterine (luminal) epithelium of pregnant rats, but not present in the uterine epithelium of nonpregnant rats. Calbindin was found also in the uterine smooth muscle and endometrial stromal cells of pregnant animals. These latter localizations were reproduced in uteri of 21-day- old nonpregnant rats by administration of tamoxifen or physiological doses of estrogens. Estrogen and tamoxifen produced half-maximal increases of uterine calbindin at daily doses of 0.1 and 10 micrograms, respectively, and maximal responses at 0.3 and 40 micrograms/day. Testosterone and progesterone, at doses which increased the growth of the uterus, did not induce calbindin-D, and both hormones blocked estradiol's effect on uterine calbindin-D appearance. The epithelial localization of calbindin in pregnant uteri was not reproduced in nonpregnant animals by either estradiol (3 micrograms/day) or progesterone (1 mg/day). The localization of calbindin in uterine epithelium during pregnancy appears to be dependent upon an as yet unknown factor. In view of the large surface area of the luminal epithelium in pregnant animals, and the pregnancy-related expression of calbindin in these cells, we propose that uterine epithelium plays an important role in transport of calcium during pregnancy.

This article has been cited by other articles:

				G.-S. Lee, H.-J. Kim, Y.-W. Jung, K.-C. Choi, and E.-B. Jeung Estrogen Receptor {alpha} Pathway Is Involved in the Regulation of Calbindin-D9k in the Uterus of Immature Rats Toxicol. Sci., April 1, 2005; 84(2): 270 - 277. [Abstract] [Full Text] [PDF]

				Y.-W. Jung, E.-J. Hong, K.-C. Choi, and E.-B. Jeung Novel Progestogenic Activity of Environmental Endocrine Disruptors in the Upregulation of Calbindin-D9k in an Immature Mouse Model Toxicol. Sci., January 1, 2005; 83(1): 78 - 88. [Abstract] [Full Text] [PDF]

				G.-S. Lee, K.-C. Choi, H.-J. Kim, and E.-B. Jeung Effect of Genistein As a Selective Estrogen Receptor Beta Agonist on the Expression of Calbindin-D9k in the Uterus of Immature Rats Toxicol. Sci., December 1, 2004; 82(2): 451 - 457. [Abstract] [Full Text] [PDF]

				G.-Y. Nie, Y. L. Jian Wang, H. Minoura, J. K. Findlay, and L. A. Salamonsen Complex Regulation of Calcium-Binding Protein D9k (Calbindin-D9k) in the Mouse Uterus During Early Pregnancy and at the Site of Embryo Implantation Biol Reprod, January 1, 2000; 62(1): 27 - 36. [Abstract] [Full Text]

				K. Tatsumi, T. Higuchi, H. Fujiwara, T. Nakayama, K. Itoh, T. Mori, S. Fujii, and J. Fujita Expression of calcium binding protein D-9k messenger RNA in the mouse uterine endometrium during implantation Mol. Hum. Reprod., February 1, 1999; 5(2): 153 - 161. [Abstract] [Full Text] [PDF]

				L. Nikitenko, G. Morgan, S. I. Kolesnikov, and F.B. P. Wooding Immunocytochemical and In Situ Hybridization Studies of the Distribution of Calbindin D9k in the Bovine Placenta Throughout Pregnancy J. Histochem. Cytochem., May 1, 1998; 46(5): 679 - 688. [Abstract] [Full Text]

				C. S. Kovacs, L. L. Chafe, M. L. Woodland, K. R. McDonald, N. J. Fudge, and P. J. Wookey Calcitropic gene expression suggests a role for the intraplacental yolk sac in maternal-fetal calcium exchange Am J Physiol Endocrinol Metab, March 1, 2002; 282(3): E721 - E732. [Abstract] [Full Text] [PDF]